Printed circuit board or card for direct chip attachment and fabrication thereof

Abstract

A printed circuit board or card for direct chip attachment that includes at least one power core, at least one signal plane that is adjacent to the power core, and plated through holes for electrical connection is provided. In addition, a layer of dielectric material is adjacent the power core and a circuitized conductive layer is adjacent the dielectric material, followed by a layer of photosensitive dielectric material adjacent the conductive layer. Photodeveloped blind vias for subsequent connection to the power core and drilled blind vias for subsequent connection to the signal plane are provided. Also provided is process for fabricating the printed circuit board or card for direct chip attachment.

What is claimed is: 
     
       1. A printed circuit board or card for direct chip attachment which comprises at least one power core, at least one signal plane adjacent to said power core, plated through holes to electrically connect said at least one power core and said at least one signal plane; layer of dielectric material adjacent said power core, circuitized conductive layer adjacent said dielectric material; a layer of photosensitive dielectric adjacent said conductive layer; photodeveloped blind vias for subsequent connection to said power core; drilled blind vias for subsequent connection to said signal plane. 
     
     
       2. The printed circuit board or card of claim 1 which includes a 4S3P triplate composite. 
     
     
       3. The printed circuit board or card of claim 1 which further includes at least one integrated circuit chip directly joined to it and wherein said at least one integrated circuit chip is electrically connected to a signal plane and power core of said board or card. 
     
     
       4. The printed circuit board or card of claim 1 wherein said chip is joined thereto with solder. 
     
     
       5. The printed circuit board or card of claim 1 wherein the photodeveloped blind vias are about 0.5 to about 1.5 mils deep and the drilled blind vias are about 6 to about 14 mils deep. 
     
     
       6. The printed circuit board or card of claim 1 wherein said blind vias are plated with an electrically conductive layer.